11.4 Trigonometric Functions
Definitions
Sine, cosine and tangent are terms designating the ratios of sides of
right triangles. In this case:
sin α = a / c
Sine:
cos α = b / c
Cosine:
tan α = a / b = sin α / cos α
Tangent:
where
c is the side opposite the right angle
a is the side opposite the angle α
b is the third side.
The TNC can find the angle from the tangent:
α = arc tan (a / b) = arc tan (sin α / cos α)
Example:
a = 25 mm
b = 50 mm
α = arctan (a / b) = arctan 0.5 = 26.57°
Furthermore:
a² + b² = c² (where a² = a x a)
c
=
(a² + b²)
HEIDENHAIN iTNC 530
c
a
b
537